Nasolabial Cyst: a Diagnostic Dilemma

Nasolabial cyst or klestadt’s cyst is a rare nonodontogenic lesion occurring in the maxillofacial region. It is commonly seen in the nasoalveolar area, lateral to ala of nose. It is usually asymptomatic and is often ignored by the patient unless it enlarges in size resulting in cosmetic deformities. It is often challenging not only to maxillofacial surgeons but also to other head and neck surgeons. It is often misdiagnosed as other common dental related or odontogenic lesions and mistreated. Here we are describing such a surgically managed case as a case report and also discussing the etiopathogenesis and management.


Introduction
Nasolabial cyst is a benign slow growing extra osseous lesion usually seen in the nasal alar region which was first reported by Emil Zukerkandl [1]. Klestadt [2] had studied about the same in the year 1953 and the lesion was known as Klestadt cyst. The incidence of nasolabial cyst is found to be 0.7% among all maxillofacial cysts [3]. It is common in fourth to fifth decades of life [4].
Often these lesions have gone unnoticed or misdiagnosed, as they are not evident on common radiographs. Patient may report with clinical symptoms related to cosmetic deformity and large lesions may result in nasal obstruction. Diagnosis is usually made by clinical findings and with other imaging modalities. On extraoral examination, a swelling sized 2×2 cm with ill-defined borders was elicited, lateral to the ala of the nose. The surface was smooth, and no punctum was seen. The swelling was soft and cystic with mild tender-ness on palpation. The swelling was palpable intraorally into the buccal vestibule of the upper left canine region ( Figure 1).

Case Presentation
It was nonmobile and cystic in nature. Infective foci of dental origin were ruled out, with thermal and electrical vitality testing of teeth, Hence the possibility of a radicular cyst or dentoalveolar abscess was ruled out.    Once the lesion was exposed, blunt dissection was proceeded around to free it from the floor of nose (Figure 5). Intraoperative inspection revealed that the lesion was surrounded by a thick lining, which was opened to expose the cystic lesion ( Figure 6), surrounded the lesion. Once the lesion was freed from the nasal floor, po-   Histopathological examination showed cyst lined by double layered goblet cell rich columnar epithelium with focal squamous metaplasia ( Figure 9) and the diagnosis was consistent with nasolabial cyst.

Discussion
Nasolabial cyst is purely a soft tissue nonodontogenic cyst though it has been classified under jaw cysts. It is also termed as the mucoid cyst of nose, nasal cyst and s-   Diagnosis is usually made by clinical findings with CT or MRI. Several imaging modalities may be used.
Since without bone involvement, it is rarely identified in plain radiographs. Though MRI gives good soft tissue definition, CT is preferable as it is less expensive. Ultra sound can also be a diagnostic method and has advantages over other invasive techniques [11][12].
Surgical excision is the treatment of choice with less morbidity. An intra oral approach is ideal with good cosmetic results. Other modalities include endoscopic excision or even marsupialization [13][14]. The Neumann [15] incision is found to be useful for complete cyst excision and best access to the pyriform aperture.
Intra operative nasal mucosal perforation is a common complication which can be sutured or small perforations will heal spontaneously even if left untreated.
Such complications were not observed in our case. Recurrence is usually rare on complete removal of lining and malignant transformation has not been reported but cellular changes have been reported in some cases in literature reviews. Informed consent from patient obtained.

Conclusion
Nasolabial cysts are rare soft tissue cysts less commonly seen in the population. The differential diagnosis of normal anatomical variation in the area and other vascular lesions should be kept in mind before surgical management. It is usually confirmed by clinical examinations aided with common imaging modalities. Surgical excision gives excellent results with less morbidity and recurrence.